In a recent image I noticed that there seemed to be a lot more hot-pixel type noise in my calibrated subs. (you may have to click the image belowe to see full version to see it).
Fortunately this was integrating out (dithering to the rescue!).
But I still was not happy with the fact that the noise was there in my subs and I started wondering if maybe my sensor was starting to go bad in someway. Further investigation showed that it started happening right after I upgraded my driver (whew, software is easier to return to China than hardware).
I upgraded the driver because it unlocks native pixel resolution so what was a 4k x 2k (4.6u px) camera turned into an 8k x 4k (2.3u px) camera. I am not using this new native resolution at the moment, so I thought the only adjustment I would have to make is to change my 1x1 bin sequence to 2x2 bin sequence (to remain at the "old" native resolution of 4k x 2k).
When I examined DARK subs from the old driver vs. the new driver it turns out that the new driver is actually less noisy than the old driver as measured by some image analysis tools, but even so it was producing these tiny subtle artifacts. So I re-shot a set of DARKs for the image I was working on and it fixed the hot-pixel like artifacts!
So "fortunately" it is cloudy so I committed my camera for the last 18 hours to re-take my dark library
Just thought I would pass this along for other 294mm users.
Edited by ryanha, 27 January 2021 - 09:10 AM.